For several generations now it has been known to use concrete blocks of a standard size in the construction of walls, homes, apartment houses, office buildings and many other structures. Although block size can vary in accordance with the particular use, one standard size of concrete block measures 8".times.8".times.16", and has two rather large cavities separated by the center web of the block. Further, for reasons of strength, it is well known to place the concrete blocks in a staggered relationship when constructing a wall, with one layer or tier of blocks offset by approximately 8" from the tier directly below it. The configuration of these standard size concrete blocks is such that the cavities of the numerous blocks used in the construction of a wall are vertically aligned.
Many building codes pertaining to both residential and commercial buildings require a special construction technique where one wall portion intersects another wall portion, such as in a 90.degree. relationship. Reinforcing bars (rebar) are frequently inserted into the block cavities defined at the corners where one wall intersects the other. Concrete is then poured into the intersecting cavities of the blocks located at such corner. Another important constructional technique required by most building codes is the pouring of a lintel along the top of the substantially completed block wall. In this instance, channel-type concrete blocks are used as the top member of each wall portion, with rebar placed horizontally in the aligned channels extending along each wall portion. Bent rebar is used at each corner. Concrete is then poured into the channel-type concrete blocks located along the top of each wall, with the bent rebar placed at each corner for preventing the corners from separating. This type of construction is much stronger than would have been the case if the concrete blocks had not been topped off with poured concrete, and the intersecting corners had not been suitably reinforced.
In addition, various methods for providing lightweight and insulating walls through a concrete form construction are also known. Such efforts have been made to avoid the cost and labor expense involved in the creation of walls constructed of concrete blocks. U.S. Pat. Nos. 3,788,020 for a "Foamed Plastic Concrete Form With Fire Resistant Tension Member" and 3,552,076 for a "Concrete Form" to Gregori are examples of such methods. A self-supporting concrete form of foamed polymeric material is molded in one piece and includes two spaced longitudinal walls. Partitions are used along the length of the concrete form in order to form vertically disposed apertures for receiving molten concrete. Although it is known to use reinforcement for the concrete poured into vertically disposed apertures, it is to be seen that typical molds are not much taller than the height of conventional concrete blocks, which extends the length of time needed for the creation of a wall. Further, there is a need for a trough-like recess extending along the upper section of such molds for receiving molten (wet) concrete, and further need for a technique wherein a builder is able to economize in the use of concrete by selecting only certain vertically disposed apertures of his molds to receive the molten concrete. The '020 patent discloses the use of metal members bridging between the side wall members of the concrete form, thus increasing labor costs as well as material costs.
U.S. Pat. No. 3,872,636 to Nicosia, entitled "Light Weight Load Bearing Metal Structural Panel" and the U.S. Pat. No. 4,223,501 to DeLozier, entitled "Concrete Form," disclose the use of concrete forms of lightweight material typically requiring metal members for strengthening purposes, which necessarily increase the cost of materials and labor.
By way of further example, U.S. Pat. No. 4,604,843 to Ott et al., entitled "Lost-Form Concrete Falsework" discloses the use of insulating slabs of foam material that are held in an upright orientation in a spaced apart relationship so that concrete can be poured therebetween. The use of a ladder-like elements for holding the slabs of foam material in the properly spaced relationship causes such a wall form to be quite heavy prior to pouring the concrete, and the amount of concrete needed in the construction of the wall cannot be effectively varied in accordance with the needed strength of the wall. U.S. Pat. No. 4,879,855 to Berrenberg, entitled "Attachment and Reinforcement Member for Molded Construction Forms" discloses a form held together by expanded metal mesh. Such arrangements can be expensive, especially when one cannot select a desirable amount of concrete sufficient for meeting the needs of the wall. Similar techniques are suggested in U.S. Pat. No. 4,889,310 to Boeshart, entitled "Concrete Forming System" in which opposed polystyrene panels are stacked to form a pair of parallel, spaced apart walls held apart by tie members, with concrete to be poured between the members. As a result, an unnecessarily heavy wall results, rather than a lightweight sufficiently load-bearing wall in which the amount of concrete utilized in the wall can be selectively modified.
Typically, the teachings in the art, as suggested by the above reference patents presented by way of example, do not provide a rapid construction of load-bearing walls, wherein the amount of concrete utilized in the wall can be varied in accordance with the need for strength.